diff --git a/06.understand_sentiment/image/formula_lstm_2.png b/06.understand_sentiment/image/formula_lstm_2.png
index 3ea724d7e2bb0bc2e81b3f5eae03b90c6d39bd83..a6401dd2464c234453160bee9e0d0f8ea2f2d702 100755
Binary files a/06.understand_sentiment/image/formula_lstm_2.png and b/06.understand_sentiment/image/formula_lstm_2.png differ
diff --git a/06.understand_sentiment/image/formula_rnn_2.png b/06.understand_sentiment/image/formula_rnn_2.png
index f53a657b2811ae0f3a15dc7ff5edde4caed7de9b..ca8ffc8bbb2efdba3cd582dfc23ef9c136e582d5 100755
Binary files a/06.understand_sentiment/image/formula_rnn_2.png and b/06.understand_sentiment/image/formula_rnn_2.png differ